1. Field of the Invention
The present invention relates to an analog electronic timepiece capable of simultaneously displaying a time and a date.
2. Description of Related Art
Conventionally, there has been an analog electronic timepiece capable of displaying a date together with a time. In usual, such an electronic timepiece as described above includes a date indicator as a dial plate rotatably provided under a dial plate, and among marks indicating dates and provided on a peripheral edge portion of the date indicator, selectively exposes any thereof from a transparent small window provided on the dial plate, and thereby displays one date.
In the analog electronic timepiece, there are: a case where, owing to an external factor such as an influence of an external magnetic field and acceleration generated by a strong impact and the like, a motor that rotates hands does not operate normally, and hand positions memorized in a memory inside the timepiece and actual hand positions are shifted from each other; and a case where a power supply is reset and information about the memorized hand positions is lost. In this connection, an analog electronic timepiece has been heretofore developed, which has a function to periodically confirm that the positions of the respective hands are appropriate, and to correct the positions concerned when the hands are shifted from such appropriate positions. For example, in Japanese Patent Laid-Open Publication No. 2011-122902 (corresponding to US 2011/0141858 A1) and Japanese Patent Laid-Open Publication No. 2011-220872 (corresponding to US 2011/0249538 A1), technologies for detecting positions of a second hand and a minute hand surely and rapidly is disclosed.
Meanwhile, there is an analog electronic timepiece in which a configuration related to such detection of the hand positions is not provided for the date indicator, because a positional shift is less likely to occur since torque required for a rotation operation is large, because it is difficult to visually recognize an extremely small shift since a rotation angle per step is small, because no problem occurs on display information even if some positional shift occurs therein since the display information is a letter indicator or the like, and so on, whereby electric power consumption is suppressed, and a size increase is suppressed.
However, in the conventional configuration related to the detection of the hand positions, it is determined by mistake that the hands are located at normal positions even in a situation where the hands are left stopped at positions where position confirmation of the hands is performed. Hence, in an analog electronic timepiece having a configuration in which a hand provided with no position detecting mechanism rotates in conjunction with a hand provided with a position detecting mechanism, there is a case where a long time elapses without perceiving that the operations of the hands are stopped, and a correct position of the hand provided with no position detecting mechanism is lost.
The present invention provides an analog electronic timepiece capable of returning the hand, which rotates in conjunction, to the correct position with ease after the operation thereof is resumed even in the case where the hand does not operate normally for a long time.